ATMs are used, for example, to dispense cash and for depositing cash or cheques. An ATM usually comprises a fascia that is hingedly attached to a chassis. Typically, the fascia will include a number of slots or apertures that are aligned with modules or components of the ATM, mounted within the chassis. For instance, the fascia may include: a display aperture through which a display is visible; a slot through which a customer inserts a magnetic stripe card encoded with the customer's personal and account data; a slot through which cash is dispensed; and, a slot through which cash or cheques are deposited. The fascia also typically includes an encrypting keypad and function defined keys (FDKs) associated with the display.
Fraudsters have devised a number of schemes for stealing customers' magnetic card data or cash. One scheme, known as “skimming”, involves fixing a magnetic read head to the fascia, which reads the magnetic stripe on a customer's card as it is inserted into or retrieved from the machine, and stores and/or relays the read data to a remote location. Another scheme involves fixing a cash diverting mechanism to the fascia which diverts a customer's cash as it is dispensed from or deposited into the ATM.
A foreign body is anything applied, fixed, fitted or adhered to or that settles on, engages or contacts the fascia of an ATM after it has been commissioned, that was not put there by an authorised party for a legitimate reason, although the term “body” includes not only solid objects but also liquids in whatever form (droplets, films, puddles etc.). There are two types of foreign bodies: those that are non-benign, that is, intended to defraud, cause disruption or deception, such as magnetic read heads, and those that are benign, such as rainwater.
Principally with a view to counteracting fraud, ATMs have been equipped with sensors that detect foreign bodies. One particular sensor works by determining changes in capacitance caused by a foreign body. Capacitance sensors are good for detecting foreign bodies made of metal, but poor at detecting foreign bodies made of non-metallic materials such as plastics. Fraudsters are increasingly using non-benign foreign bodies made of non-metallic materials.